What does that even mean? Over time this model can't support its own weight.

They could put it back in its plexiglass truss, I suppose that would help (in principle it was like those slings that are used to suspend broken legs horizontally; one bar passed under the saucer and I believe slings supported the nacelles).

Many more-esteemed works of art are cleaned, restored, and displayed to the public.

Every exhibit is different. If curators believed that the display of an irreplacable painting would destroy it, they wouldn't put it on display. Period, full stop.